docs: def check_dimension_names(self, ds):
          '''
          Checks variables contain no duplicate dimension names.
  
          CF §2.4 A variable may have any number of dimensions, including zero,
          and the dimensions must all have different names.
  
          :param netCDF4.Dataset ds: An open netCDF dataset
          :rtype: compliance_checker.base.Result
          '''
          fails = []
          total = len(ds.variables)
  
          for k, v in ds.variables.items():
              dims = defaultdict(int)
              for d in v.dimensions:
                  dims[d] += 1
  
              for dimension, count in dims.items():
                  if count > 1:
                      fails.append("%s has two or more dimensions named %s" % (k, dimension))
  
          return Result(BaseCheck.HIGH, (total - len(fails), total), self.section_titles['2.4'], msgs=fails)